Trans-axle drive assembly



June 29, 1965 M, QLLMAN 3,191,447

TRANS-AXLE DRIVE ASSEMBLY Filed Oct. 27, 1961 4 Sheets-Sheet 1 IN VENTOR.

A TORNEYS' June 29, 1965 M. L. oLLMAN 3,191,447

TRANS-AXLE DRIVE ASSEMBLY 4 Sheets-Sheet 2' 'Filed oct. 27. 1961ATTORNEYS Junef29, 1965 M. L. oLLMAN 3,191,447

TRANS-AXLE DRIVE ASSEMBLY Filed oct. 27, 1961 4 sheets-sheet s IN VENTOR.

ATTORNEYS' June 29, 1965 M. L. oLLMAN 3,191,447

TRANS-AXLE DRIVE ASSEMBLY Filed Oct. 27, 1961 4 Sheets-Sheet 4 IN VENTOR.

ATTORNEYS -facturing `of one or both of .the units lthemselves. thoseinstances in which manufacturers have designed United States Patent O3,191,447 TRANS-AXLE DRIVE ASSEMBLY Melvin L. Ullman, Detroit, Mich.,assigner to Dura Corporation, Oak Park, Mich., a corporation of MichiganFiied Det. 27, 1961, Ser. No. 148,064

2t) Claims. (Cl. 74--700) This invention relates to axle driveassemblies in general, .and more particularly to a combinationtransmission Vand .axle drive assembly for multiple purpose use.

Small equipment manufacturers have great need for compact powertransmission and .axle drive assemblies to service small motiveequipment such as garden tractors, lawn mowers, golf carts and the likewhere size, weight, initial and maintenance expenses are of primeimportance. 'Io date such manufacturers have had to buy separatetransmission and axle drive assemblies, usually from different sourcesfor better prices, or t-o tool-up for .the manuand .built .suitabledrive assemblies for their own purposes they have done so to suit theirown particular requirements .and have 'accordingly not made available adrive assembly having general use and acceptance for the many purposesit might serve.

As will be appreciated, a universally acceptable axle drive .assemblymust provide for multiple forward drive speeds, reverse drive and yadifferential drive of the mctive axles. Further, .a suitable means forshifting must be provided and provision made for relatively troublefreeoperation. These and numerous other desirable features must be providedfor by the use of a minimum `of expensive parts and within a compact.assembly to obtaina commercially acceptable product where volumeproduction will enable still further price reductions to purchasers andenable competition with existing equipment of like kind.

It is an object of this invention to provide a transaxle drive assemblywherein a compact multiple speed transmission and axle drive assemblyare accommodated within an integral housing.

It is an object of this invention to make use of and `improve upon thestandard wringer roll transmission,

known for its use in early washing machines, to obtain 4a direct forwardor reverse drive through the side gear gear clutching and drive lineconnecting means operable between relatively fixed operating and neutralpositions that precludes inadvertent disengagement or engagement yetsimple operational control thereof.

A still further object of this invention is to provide a simplegearshift lever control to accomplish 4the necessary directional Iandspeed changes required to be made and lsuch as enables coordinatedactuation of different Idrive clutching means and precludes simultaneousactuation thereof.

Another important object -of this invention is .to provide a new andnovel axle drive assembly particularly suited for trans-axle use whereina differential axle arrangement is powered by -a bevel gear carryinggear member supported on and between the drive axles.

3,191,447 Patented June 29, 1965 ice In .this latter respect, it is alsoan object of this invention to provide a diiferential axle drive meansincluding means for minimizing inadvertent reactionary drive between the-axle members.

These and Iother objects and .advantages in the practice 4of this.invention will be more apparent upon reading the followingspecification having reference to the accompanying drawings showing apreferred embodiment of this invention.

In the drawings:

FIGURE 1 is a top plan view of the trans-axle assembly -of .thisinvention;

FIGURE 2 is a cross-sectional view of the trans-axle assembly shown byFIGURE l as seen in the plane of line 2--2 thereon and looking in thedirection of the arrows;

FIGURE 3 is an enlarged center line cross sectional view of thetrans-axle assembly of this invention as seen .in the plane `of line 3 3in FIGURE 2 and looking in the direction of the arrows thereon;

FIGURE 4 is an enlarged center line cross sectional View of thetrans-axle assembly of this invention as seen in the plane of line 4 4of FIGURE 2 and looking in the direction of the arrows thereon;

.FIGURE 5 is a furtherenlarged cross sectional view of .the gearshaftcontrol feature as seen .in the plane of line 5-5 -of FIGURE 3 andlooking in the direction of the arrows thereon;

FIGURE 6 is an enlarged .and fragmentary side plan view of thedifferential axle drive assembly;

FIGURE 7 -is an enlarged det-ailed View of a pinion gear retainingfeature provided in the differential axle drive gear as seen in theplane of line 7-7 of FIGURE 6, looking in the direction of the arrowsthereon.

As will be hereinafter described in further detail, the trans-axle ofthis invention makes use of a combination transmission and axle housingwherein bevel tooth side gears are provided in the transmission part anda reciprocal clutch member is disposed therebetween for engagement withone or the other thereof. A differential axle is provided within theaxle housing part and is driven by a pinion gear carrying bull gearengaged with the side gear clutching member. This alfords the option ofa forward or reverse drive. In addition, the sideV gears areprovidedfwith spur gear Ateeth and are each part of separate gear trainsselectively connected to the axle driving bull gear by a second clutchmember to obtain a 2nd or 3rd speed forward drive. By a novel gearshiftarrangement one or the other of `the clutch member is engaged with oneof the side gears for selected lst, 2nd or 3rd forward or reverse driveof the output axles.

The .trans-axle assembly of this invention makes use of a single housing10 which includes ltransmission and axle housing portions. The housingis a two part structure divided at the center line 12. Within thetransmission housing porti-on 14 is disposed the dilferent gear members`and the gearshift mechanism for obtaining the multiple forward andreverse speeds which have been mentioned.

The vaxle housing portion of the integral housing 10 includes the axleVhousing sleeves 16 and .18 each having part of the transmission housingportion 14 provided on the .adjacently disposed ends thereof andstructurally reinforced by the webs and mounting flanges 20.

Drive axles 22 and 24 are journaled within suitable bearings 26 and 28within the axle housing sleeves 16 and 18. Axle driving bevel gears 30and 32 are provided on the ends of the axle shafts. A bull gear 34 isrotatably mounted and supported on the adjacently disposed and -alignedends 4of the .axle shafts and serves as a carrier for beveled .toothedpinion gears 36 disposed for drive engagement with the axle gears 30 and32.

.the gear 74 in the position shown.

A pair of side gears Sii and It@ are mounted within the transmissionhousing portion .14. The side gears include beveled gear teeth 42 and4.4, respectively, which are engaged with and driven by :a beveled toothgear on the end -of the assembly drive shaft, which will bedescribed-later. The side gears 38 and il are `also formed to in-cludespur gear teeth 46 and d8, respectively.

The side gears 3d and d@ are mounted on a shaft Si) .provided within thetransmission housing portion. Suitable bushing members 53 .and 54 areprovided on the ends of the shaft ywithin receptive parts of the housingwalls. The side gears 38 `and d@ are freely rotatable on theshaft Siland are retained in the positions shown by suitable lock ring o r otherconventionally known'means.

A clutch member S6 is rotatably disposed onthe shaft Sil between theside gears 38 and 40. In this 'instance the clutch membe-r 56 is a dogpawl lclutch having its ends formed for engagement with lsuitable webs58 and o@ provided on the adjacently disposed sides of the side gears 38and'iil, respectively. The clutch member 56 is (also provided withrspurgear t-eeth 62 and is disposed 'inengage ment with the axle shaftdrivingbull gear 34. The clutch member 56 is provided withacircumferential 'groove 64 which is receptive of means for shifting theclutch member between neutral and side gear engaging positions by meanswhich will be described later.

FIGURE 3 shows a drive shaft-member 66 journaled within a receptivebearing 67 within the trans-axle housing and having a beveled drive gearpro'vided on the end 'thereof and disposed for engagement with the sidegears 38 'member 70 provided on a shaft 72. The gear member 7@ is partof .a gear train assembly which includes another spur Vgear toothedmember '74 provided on a 4shaft 76'and disposed behind another geartoothed member 9ilon the same shaft and which is in turn engaged withthe bull gear 342. j Y

j FIGURE 4 shows the drive shaft' 66 having its beveled drive gear `68engaged with the side `gear 46' -and the clutch memberSo mounted withthe side `gearlon the shaft 59 `and disposed for driving engagementwith'thebull gear 34. A gear member dit provided on shaft 76'is disposedfor driving engagement with the spur gear teeth 48 of the Aside gear 30.The gear toothed member 9i), which is yet to be described, is providedon the same shaft and is disposed ffor driving engagement with thebullgear 34 which drives the axle shafts 22 `and Z4. A

Referring now to FIGURE 5, the shaft 76- is shown to `be mounted within4suitable journal bearings S6 and 88 provided within the housing sidewalls `and to have the gear toothed member 90, which is also a clutchmember,

Vprovidedthereon andbetween the gear toothed members 74 andStl whichwere previously mentioned. The gear ,toothed clutch member 90 is engagedwith the bull gear 34 and includes `a dog pawl ends which are engageablelwith webs v92 and 94 provided on the adjacent sides of teeth 100 forengagement with the gear teeth of the bull gear 34 and to have acircumferential groove 102 provided therearound.

A lock` ring 104 is 'shown provided on shaft 76 to hold As will beappreciated, like means may be used wtih other'of the gear members.

A C-ring groove is provided in the clutch member 166 d and is receptiveof .a C-ring 1% which is in turn receptive within any of the C-ringgrooves 11@ provided in the shaft 76 for axial positioning of the clutchmember between a neutrally disposed position and one wherein it isengaged with one or the other of the gear members 74 or Sil.

As should be appreciated from the description thus far, Athe shifting ofthe clutch mem-ber 56 for eng-agement with either of the side gears 38or dit will provide either forward or reverse drive through theengagement between the clutch member and the bull -gear 34. Further,engagement of the second clutch member 99 with either ofthe gear members74 or Si?, while the first clutch member 56 is in a neutral position,will provide a second or third forward drive connection through the geartrain engagement of such gear members between the bull gear 34 and thespur gear teeth of one or the other of the side gears 38 and dit.

The clutch members Se and 9i) are selec-tively operated by a gearshiftlever 112 extending into the transmission rpart 14 of the trans-axlehousing 10 and received through a ball socket pivot joint 114. The ballsocket `arrangement 114 includes trunnion pins 116 which are guidedwithin elongated slot-s 118 in the housing side walls to en- Y able alimited degree of transverse movement in comparison with the -movementto be described as necessary to shift the clutch members into theirdifferentpositions. This limited transverse freedom of movement issuficient toenable the tongueendll of the shift lever 112 to clear acircumferential gr-oove 121 provided within-the shaft 72 and tothereafter move axially onxone side or'the other of such shaft to shiftcertain clutch actuating members hereafter described.

A clutch actuating gearshift member 122 is mounted on the shaft 72 anddisposed for engagement by the end of the gearshift lever 112. A`similar gearshift member 128 vis disposed on the same shaft and inoverlapping relation to the other gearshift member 122. These two tionof the other gearshift member 12% which is similarly formed andsupported on the shaft 72. The gearshift member 122 includes a dependingbifurcated part 125 dis- 'posed centrally thereof and which is receivedwithin the circumferential groove 192 in the clutch member 91D. A-similar'bifurcated part 132 on the end of an extension arm 1134 isprovided on the gearshift member 128 and is disposed for engagementwithin the circumferential groove 64 of the clutch member 56.

FIGURES 3-5 showthat the tongue end 120 of the gearshift leve-r .112must be pivoted out of the groove 1291 in theshaft 72 before it can bemoved .axially of the' shaft ysuch .that subsequent axial movement willin turn axially shift one or the other of the gearshift members `122,128 land effect engagement of one of the clutch members 56, 99 for thedesired forward, reverse, second or third speed forward drive which isdesired. Since the tongue end of the shift lever 112 must be returned tothe location of the circumferential groove 121 in the shaft 72 before itcan cross over vbetween the two gearshift members 1.22 and 128, only oneor the other of the clutch members will be `actua-ted at any one timeand the yother will be in the neutral position. Accordingly, thegearshift arrangement is essentially trouble-proof.

Upon rotation of the bull gear 34, through drive engagement effected byeither of the clutch members 9d or 56, the beveled toothed pinion gears36 will rotate with the bull gear and will drive the bevel gears 30 and32 on the ends of the drive axles 22 and 24. If either axle should ymeetresistance the beveled toothed pinion gears will be result ofunimportant and minor differences in drive resistance in the driveaxles. Such means are best shown `by FIGURES 6 and 7.

The bull gear 34 is provided with cut-away sections 138 receptive of thebeveled toothed pinion gears 36 therein.

`The pinion gears are rotatable on a pivot pin 140 having flat sidedends 142. Transverse slots 144 are formed to receive the dat sided ends142 of the pivot pin therein. Accordingly, the pinion gears 36 are heldcentered within the bull gear principally Iby their engagement with thebeveled gears 30 and 32 on the ends of the axle shafts 22 and 24,respectively. i

The beveled toothed pinion gears 36 are spring loaded Within the gearcarrying Iaccesses 138 of the bull gear by means of a Belleville spring146 engaging the -outer disposed wall of the access and seated on awasher 148 engaging the pinion gear. This spring loading prevents freefloating of the pinion gears by assuring a degree `of fric- `tionalresistance to rotation and thereby precludes unintentional rotationofthe pinion gears 36 and reactionary ,drive of .one axle shaft due to aslight difference in drive resistance between the two axle shafts.

Although a preferred embodiment of this invention has been shown anddescribed, it will be appreciated that certain modifications andimprovements are within the scope of teachings set forth. Suchmodifications and improvements as are within the teachings and spirit ofthis invention and are so specifically excluded by the language of thehereinafter appended claims are Ito be considered as inclusivethereunder.

I claim:

1. A trans-axle assembly, comprising: an integral transmission and axlehousing having a pair of coaxially disposed and spaced gear membersprovided therein, means engaged with said gear members for driving themin opposite rotational directions, separately mounted gear toothedmembers provided between said oppositely driven gear members, axledriving means including a gear member engaged with said gear toothedmembers, and means for alternatively engaging one of said gear toothedmembers with one of said oppositely driven gear members.

2. A trans-axle assembly, comprising: an integral transmission and axlehousing having'a pair of coaxially disposed and spaced gear membersprovided therein, means engaged with said gear members for driving themin opposite rotational directions, a pair of separatelyoperable andaxially reciprocal clutch members disposed between said gear members andeach having a gear toothed periphery, axle drive means including a pairof drive axles having bevel gears provi-ded on theadjacent ends thereof,a bevel gear carrying bull gear rotatable on said drive axles andoperatively engaged with said drive axle bevel gears, said bull gearalso -being operatively engaged to said clutch members, and means foralternatively engaging one of said clutch members with one of saidoppositely driven gear members for driving said axles therethrough.

3. The trans-axle assembly of claim 1 comprising separate speed changinggear train assemblies operatively connected to said oppositely drivengear members and each including a gear member coaxially disposed andspaced with relation to a gear member of the other thereof, and one ofsaid gear toothed members being reciprocal between said last mentionedgear members for operatively engaging one thereof with said axle drivinggearv member.

4. An axle drive, comprising: a housing having a pair of coaxiallydisposed and spaced side gear members and a single axle driving outputgear provided therein, a clutch member provided between said side gearmembers for selective engagement therewith and between and disposed indrive engagement with said output gear, a separate gear member in driveengagement with one of said side gear members, a second clutch memberoperatively engaged with said output gear and disposed for selectiveengagement vwith said separate gear member, and operative means forselective actuating said different clutch members and Cil cooperativelydisposed for interrelated actuation thereof requiring the disengagementof one prior to the engagement of the other thereof with a receptivegear member.

5. A trans-axle assembly comprising: an integral transmission and axlehousing including a pair of coaxially disposed and spaced bevel sidegears having a bevel gear engaged therewith for driving said side gearsin opposite ro- `tational directions; a pair of axle shafts supported insaid `housing and having bevel drive gears provided near the adjacentends thereof, a bevel gear carrying `spur gear toothed member rotatablysupported on and between said axle shafts and drivingly engagedtherewith through said bevel drive gears; a spur gear toothed dog pawlclutch `member rotatably mounted and reciprocal between said bevel sidegears and operatively engaged with said axle driving gear member; meansengaging said clutch member and operative thereof into drivingengagement with Aeither of said side gears; spur gear tooth portionsprovided `each having an axially reciprocal clutch member disposedbetween the gear members thereof, the gear members of said first pairbeing driven by a common drive means, the

`gear members of said second pair being separately rotatable andoperatively connected to different of the gear members of said iirstpair, said clutch members each including gear teeth and being engagedwith a common output gear member,` a shaft having separate clutchengaging and actuating members guided thereon and separately operable onrespectively opposite sides of said shaft, a single lever member forengagement with and operation of said clutch actuating members, saidshaft including an undercut portion, said lever member being of a lengthprecluding passage between opposite sides of said shaft except throughsaid undercut portion and said clutch actuating members being eachformed to require the return thereof to a neutral position on saidsupporting shaft preceding `the vpassage of said lever membertherebetween.

7. A gear shift mechanism, comprising: a shaft having separate gearclutch operating members coaxially disposed thereon and operable onrespectively opposite sides thereof, a common single lever memberpivotally mounted and having one end thereof disposed for engagement andoperation of different of said clutch operating members on oppositesides of said shaft, said shaft including an iindercut portionintermediate the ends thereof, said lever member being of a lengthprecluding passage of said one end between opposite sides of said shaftexcept through said undercut portion, and said gear clutch operatingmembers being cooperatively formed to each require the return thereof toa neutral clutch operating position preceding the passage of said levermember for engagement therebetween.

I8. A differential axle, comprising: an axle housing, aligned axlemembers having their adjacent ends received and supported within saidhousing, bevel toothed gear members provided on the adjacent ends ofsaid axle shafts, an `axle driving bull gear rotatably supported on theadjacent ends of said axle shafts, pinion gear receptive cutoutsprovided within said bull gear, and bevel toothed pinion gears rotatablysupported and axially self-adjustable within said cut-outs and disposedin driving engagement with said axle shaft gear members.

9. The differential axle of claim 8, including; radially disposed slotsprovided in said bull gear on opposite sides Y 7 Y of said 'cut-outs,and pinion gear supporting pins having f.flat sided ends received insaid slots for permitting relative axial freedom of movementf-or saidpinion gears be'- tween said'axle'shaft gear members.

l10. The differential axle of claim 9, including; means providedbetween'said pinion gears and the outer disposed side of said cnt-outsfor biasing said pinion gears in *frictional engagement with the innerdisposed sides thereof.

11. A trans-axle assembly, comprising: an integral transmission and axlelhousing including a Vpair of coaxially disposed and spaced gear membershaving drive means provided therebetween Vand operative thereof in op--posite rotational directions, axle driving means provided in saidhousing and including means of selective operational engagement withdifferent of saidspaced gear mem- 'bersfo'rforward and reverse drivethereof and neutral 'posi- 'tioning relativethereto, and speed changingmeans disposed within said housing for selective operational engagementwith one of said spaced'gear members and said axle driving means uponvthe neutral lpositioning of said first mentioned spaced gear engagementmeans.

12. A multiple speed forward and reverse drive assembly, comprising: 'apairJ of 'bevel toothed side gear members disposed in coaxial'spacedrelation and having common drive means engaged therewith forrotationtherei of in selectively opposite directions, a spur gear toothed clutch'member disposed foraxial reciprocation between Ysaid side gear membersand selective splined end engagement therewith 'and for neutral4positioning therebetween, l

a spur gear toothed Ioutput drive member having said spur gear toothedclutch memberioperatively engaged 'therewith, and spur toothed geartrain means operatively 'engaged to saidside gear members vand-disposedfor speed y ratio changing engagement with said output drive membersoffsaid gear train means disposed next adjacent said output drive memberfor selected splined end engagement therewith and neutral'positioningtherebetween, and said latter clutch member beingoperatively engaged'to said output drive member. l

x14. The multiple speed forward and reverse drive asf50 d 'sem-bly -ofclaim 13 including, common .operative means Vpivotally mountedandhavingan end `thereof selectively operative of said clutch members andfor the neutral positioning of one thereof prior to disposing the otherthereof kin an operative position.

15. rThe multiple speed forward and reverse drive assembly of claim 14including, coaxially disposed means operatively engaged with saiddifferent clutch members -and cooperatively disposed for selectiveactuation by -said common operative means last mentioned.

The multiple speed forward and reverse drive assembly of claimlincluding, said coaxially disposed means including yoke membersVcooperatively disposed and having the pawl ends thereof operativelyengaged to said different clutch members.

17. A gear shift mechanism, comprising: a shaft hav- 'ing separateclutch operative means provided on differ- 'ent sides thereof, commonmeans transferable between -different sides of `said shaft and axiallyreciprocal rela- 520 i tive thereto. for selective and separateoperative engage- V'ment with said clutch operative means, and meansdisposed for engagement by said common means and permitting the transferthereof between said different shaft -sides only following the neutralpositioning of said clutch loperative means.

18. The '-gear shift mechanism of claim 17, vsaid last vmentioned meansbeing provided in one of said shaft and 'clutch operative means.

19. The gear shift mechanism of claim 17, said last mentioned meansincluding a by-pa'ss yprovided in said shaft permissive of the passageofsaid common means 'only therethrough.

A26'. The gear shift mechanism, of claim `11.7, said last mentionedmeans including an annular groove provided about said shaft and saidVcommon means including a -lever pivotally mounted and'having an end`thereof opera- -tive of said Aclutch means transferablelonlytherethrough.

References Cited bythe Examiner UNITED STATES PATENTS 'DON A. WATE,'Primary Examiner.

1. A TRANS-AXLE ASSEMBLY, COMPRISING: AN INTEGRAL TRANSMISSION AND AXLEHOUSING HAVING A PAIR OF COAXIALLY DISPOSED AND SPACED GEAR MEMBERSPROVIDED THEREIN, MEANS ENGAGED WITH SAID GEAR MEMBERS FOR DRIVING THEMIN OPPOSITE ROTATIONAL DIRECTIONS, SEPARATELY MOUNTED GEAR TOOTHEDMEMBERS PROVIDED BETWEEN SAID OPPOSITELY DRIVEN GEAR MEMBERS, AXLEDRIVING MEANS INCLUDING A GEAR MEMBER ENGAGED WITH SAID GEAR TOOTHEDMEMBERS, AND MEANS FOR ALTERNATIVELY ENGAGING ONE OF SAID GEAR TOOTHEDMEMBERS WITH ONE OF SAID OPPOSITELY DRIVEN GEAR MEMBERS.